Civil liberties are fundamental rights guaranteed by the Constitution, protecting individuals from government interference. These include freedoms of speech, religion, and assembly, as well as due process rights. Civil liberties have evolved through amendments, legislation, and court decisions. Key amendments like the First, Fourth, and Fourteenth shape civil liberties. Modern challenges include balancing national security with personal freedoms, addressing technological privacy concerns, and navigating issues of racial justice and LGBTQ+ rights in a changing social landscape.